selja ("to sell") is the everyday verb of markets, classifieds, and second-hand deals — and it is the mirror image of kaupa "to buy." It is a weak j-verb: a j surfaces in some forms (selja, seljum, selja) but vanishes before the front-vowel endings of the singular present (sel, selur). That alternation is the one thing to nail, because getting it wrong is the most audible mistake learners make with this verb. The preterite is the clean weak -di type: seldi.
Conjugation
Class: weak, j-class (the j appears before -a/-u endings but not before -ur/-ir). Preterite: dental -di (seldi). Auxiliary: hafa — ég hef selt "I have sold."
| Principal parts | |
|---|---|
| Infinitive | að selja |
| 3sg present | selur |
| 3sg past | seldi |
| Supine | selt |
| Person | Present (nútíð) | Past (þátíð) |
|---|---|---|
| ég | sel | seldi |
| þú | selur | seldir |
| hann / hún / það | selur | seldi |
| við | seljum | seldum |
| þið | seljið | selduð |
| þeir / þær / þau | selja | seldu |
| Person | Present subjunctive | Past subjunctive |
|---|---|---|
| ég | selji | seldi |
| þú | seljir | seldir |
| hann / hún / það | selji | seldi |
| við | seljum | seldum |
| þið | seljið | selduð |
| þeir / þær / þau | selji | seldu |
| Non-finite & imperative | |
|---|---|
| Imperative (þú) | sel! / seldu (with attached pronoun) |
| Imperative (þið) | seljið! |
| Supine | selt |
| Past participle (m/f/n) | seldur / seld / selt |
| Middle voice (miðmynd) | seljast (3sg selst, past seldist) |
The j-alternation, explained
Icelandic j-verbs carry a stem-final j that only survives before a back vowel (-a, -u) or where it sits between the stem and an -i. Before the front-vowel endings -ur and -ir of the singular present, the j is swallowed: hence ég sel, þú selur, hún selur — no j — but við seljum, þeir selja — j back again. In the past tense the j drops entirely because the dental -di ending follows a consonant: seldi, seldir, seldi, seldum, selduð, seldu. Note there is no u-umlaut here: the stem vowel is e, not a, so nothing turns to ö.
Við seljum bara lífrænt grænmeti á þessum markaði.
We only sell organic vegetables at this market.
Hann selur pylsur niðri í bæ um helgar.
He sells hot dogs downtown on weekends.
Ég sel þér bílinn á hálfa milljón.
I'll sell you the car for half a million.
Syntax: who gets what
selja takes two objects: the buyer in the dative and the thing sold in the accusative — selja einhverjum (dat.) eitthvað (acc.). This is the same frame as English "sell someone something," and it lines up exactly with gefa "give." When only the thing is mentioned, it stays accusative: ég seldi bílinn "I sold the car (acc.)."
Hún seldi nágrönnunum gamla sófann sinn.
She sold the neighbours her old sofa.
Þau seldu húsið og fluttu til Akureyrar.
They sold the house and moved to Akureyri.
seljast — to sell (of goods)
The middle voice seljast turns the focus onto the goods themselves: bókin selst vel "the book sells / is selling well." There is no agent in view — it is the intransitive "sell" of English "this model sells fast." Past tense: seldist.
Nýja platan hennar selst eins og heitar lummur.
Her new album is selling like hot cakes.
Miðarnir seldust upp á örfáum mínútum.
The tickets sold out in just a few minutes.
selja vs kaupa
selja and kaupa ("buy") are the two halves of every transaction, and learners sometimes reach for the wrong one under pressure. Keep the direction straight: money leaves the buyer (kaupa) and goes to the seller (selja). Both take the thing in the accusative; selja additionally allows the dative recipient.
Ég keypti hjólið sem þú seldir í fyrra.
I bought the bike you sold last year.
Common Mistakes
❌ Við selum grænmeti.
Incorrect — the plural keeps the j: seljum, not selum
✅ Við seljum grænmeti.
We sell vegetables.
❌ Ég selji bílinn minn.
Incorrect — selji is the subjunctive; the plain 1sg present is sel (no j, no -i)
✅ Ég sel bílinn minn.
I'm selling my car.
❌ Hún seldi sófann til nágrannans.
Understandable, but the recipient takes the bare dative, not til + genitive
✅ Hún seldi nágrannanum sófann.
She sold the neighbour the sofa.
❌ Miðarnir seldu upp strax.
Incorrect — 'sell out' (of goods) needs the middle voice seldust, not active seldu
✅ Miðarnir seldust upp strax.
The tickets sold out immediately.
Key Takeaways
- selja / sel / seldi / selt — a weak j-verb; the j shows in selja, seljum, seljið, selja but drops in sel, selur and the whole past.
- No u-umlaut: the stem vowel is e, so nothing becomes ö.
- Two objects: buyer in the dative, thing in the accusative (selja einhverjum eitthvað).
- seljast = "sell / be sold" (goods as subject); bókin selst vel, miðarnir seldust upp.
- Opposite of kaupa "buy" — keep the direction of the money in mind.
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Start learning Icelandic→Related Topics
- Weak Verbs: The Four ClassesA2 — The weak verb system — verbs that build their past tense with a dental suffix (-aði, -di, -ði, -ti) instead of a vowel change — split into four classes by their thematic vowel and present pattern, including the Class-4 j-verbs that hide a strong-looking e→a shift inside a weak conjugation.
- kaupa (to buy)A2 — Full conjugation of the weak Class-2 verb kaupa (kaupi / keypti / keyptu / keypt), with the irregular au→ey preterite vowel and voiceless -ti suffix, the benefactive kaupa sér 'buy oneself', and the contrast with selja 'sell'.